- Have taken any of the following drugs within 14 days prior to study entry: amiodarone, astemizole, bepridil, cisapride, ergot or ergot derivatives, systemic itraconazole, systemic ketoconazole, midazolam, propoxyphene, quinidine, rifampin, terfenadine, thalidomide, triazolam, or St. John's wort.